Who in this thread is denying climate change?
Your argument here makes little sense to me. Properly sited sensors have reliable, correct high temps, and that's why there's scientific standards for the ones that are used for NOAA/NWS data.
Low temps, on the other hand, vary more wildly based on location and that can't be fixed through better siting. But it does make sense that sensors that have a long period of record in a single location that has seen the least amount of changes around it are going to provide the most reliable temperature record.